Applicator for adhesives



49 $342, F, E, BAKER MDPLICATOR FOR ADHEsIvEs Filed May l, lSSQ HHEI VEPatented Aug. 4, 1942 UNITED STATES ATENT OFFICE APPLCTR FOR ADHESIVESFranklin E. Baker, Chicago, Ill. Application May 1, 1939, Serial No.271,054

4 Claims.

This invention relates to improvements in adhesive applicators andcontainers to be used in connection therewith.

Heretofore in this art bristle brushes and semirigid or slightlyflexible applicators have been :commonly used, each, however, having itsown peculiar disadvantages. The brush absorbs an excess amount ofadhesive when thrust downw-ardly into a paste or mucilage jar and thisexcess must be removed with care and only upon the exercise ofconsiderable effort before the spreading operation can .be commenced. Asthe brush spreads the adhesive a film of very irregular thicknessresults, leaving what are commonly `called brush marks and which inreality are ridges of adhesive of more than a desirable thickness. Thebristle brush has enjoyed extensive use even though it has long beenrecognized by those especially skilled in the use of adhesives, andindeed constantly advocated by them, that adhesive is most effectivelyused when applied in a very uniform thin film.

Another form of applicator which has experienced some use is thesemi-rigid or slightly ilexible rubber applicator secured to or formedat the end of a stem or handle which usually is also somewhat flexible.I have found that all such rubber applicators heretofore used have suchan amount of rigidity and springiness that the user has difficultyinmaintaining accurate control of the end of the applicator as the ratherstiff rubber wiper tends to spring out of control and has to be handledwith extreme care to prevent it from moving out of the limits of thearea intended to be covered with adhesive.

I have overcome the above named disadvantages o-f the prior applicatorsand attained new advantages by utilizing a rigid stem or handle to theend of which is secured an extremely flexible section of very thinrubber, it being so thin as to be free from any unnecessary stillness.Preferably the rubber section is cut from a sheet of rubber of uniformthickness and of such texture as will yield the desired flexibility. Thethin soft rubber bends at a right angle to the end of the l stem withoutany substantial tendency to spring back in opposition to the controlbeing exercised by the user, and it spreads a film of such thinness anduniformity as cannot be attained by any other known form of applicator,thus realizing the objective which has always been advocated but neverheretofore accomplished.

Further-more when this applicator is used in conjunction with anadhesive container, the rigid stem thereof may be readily andinexpensively secured to the inside of an ordinary bottle cover so thatwhen the container is covered nothing need protrude vabove the capexcept the head of -a small nail or tack Vwhich forms an adequate andeconomical attaching means for the stem.

Because of the extreme flexibility 0f the rubber wiper, the stem may bemade long enough to extend practically' to the bottom of the jar, thusfacilitating the removal of the entire contents of the jar when it isnearly empty.

Another advantage inherent in this invention, in addition to the new andimproved functioning of the device, arises from the `fact that theconstruction lends itself to the most economical manufacture, wherebythis invention with its hitherto unavailable advantages may now beproduced at such a low cost as to be within the reach of thosepurchasers who heretofore could not well afford the more expensive andcomplicated devices on the market.

The attainment of the foregoing advantages and others which are inherentin the invention and which will become apparent from a perusal of thisspecification comprise the vobjects of this invention.

In the drawing, Fig. 1 is a perspective of acontainer :cap havingattached thereto ah applicator made in accordance with this invention.

Fig. 2 is a central vertical sectional View of a container equipped withthe device shown in Fig. l.

Fig. 3 is a view showing the use of the appliycator when removed fromthe container.

Fig. 4 illustrates a preferred manner of using the applicator holdingthe stem substantially vertical to the surface on which the adhesive isbeing applied.

Fig. 5 is a side elevation showing the applicator in use in the samemanner as shown in Fig. 4.

Referring further to the drawing, the applicator consists of a rigidstem l which for reasons of economy is made `preferably of wood,although some other rigid and inexpensive materialrrnay -be used. Asimple kerf orslot is cut through the end of the stem and in itis snuglyfitted a-,small piece 2 of very thin flexible rubber, which lmay haveabout the thickness and flexibility of the rubber used in an automobileinner-tube or that which is used in a fairly heavy hot-water bottle,Obviously rubber of such flexibility alords no substantial resistance todeflection, consequent- 1y it does not have the stiff springy feelpossessed by the rubber applicators which have heretofore been found inthis art.

The unique construction of this applicator lends itself readily toattachment to the cap of an ordinary paste or mucilage jar such as thejar 3 having an ordinary screw cap 4. The Wooden stem I is readilysecured to the cap merely by driving a small nail or tack 5 through thethin metal cap of the jar, the head 6 of the nail being the onlyprotuberance above the bottle cap. In Fig. 2 I have shown the capequipped with a liner l which is commonly employed on such caps toprovide an air-tight seal to the jar.

It will be noted that the rigid stem extends practically to the bottomof the bottle, the rubber piece being deflected to the position shownbut without any injury thereto.

By using a simple slot in a wooden stem together with a rubber wiper ofthe character described, the snug t of the rubber in the slot issufficient to retain it permanently.

Another advantage inherent in this invention is that Where containers ofdifferent capacities and heights are required, no substantial change inthe construction of the applicator is required. It is sufficient merelyto employ a stem of suicient length to reach nearly to the bottom of thejar, no matter what its depth may be.

In using this invention the screw cap is gripped by the fingers of theuser. The stem and cap being rigidly united, the user has as accuratecontrol over the extremity of the stern as ,he would have over a pensecured to a rigid penholder. Preferably the stem is held verticallywhen applying the adhesive, although in an inclined position it willspread uniformly. But in the vertical position the applicator may bemoved back and forth more readily to facilitate rapid spreading of theadhesive and because the thin rubber has no stiffness control over it isnever relaxed.

While the drawing shows a preferred manner of attaching the rubber pieceto the applicator stem, it should be understood that it may be securedto the stem in any suitable manner consistent with the purposes of theinvention. Also while the stem is secured to the cover cap by means of asmall nail it should be understood that the invention contemplates thatit may be secured in any suitable and practical manner.

Since the rubber spreader has no substantial stiffness, the stem issubjected to no substantial lateral strain when the applicator is in useand the user is holding it by means of the bottle cap. Hence the use ofa small nail to secure the stem and cap together is made possible andpractical.

Other rubber applicators heretofore used were molded products in whichthe wiping portion has a gradually thickening upper part tapering to amolded socket or molded stem. The wiping portions of such devicestherefore do not bend readily at a right angle where they emerge fromthe heavier parts of the handles which guide their movement. The line atwhich a fairly sharp bend in such a wiper will occur varies with theamount of downward pressure which is being exerted at any instant. Theaction of the wiper and the control over it is therefore uncertain andthe pressure on the article to which the adhesive is applied varies forthe same reason. Hence, tapered wipers of the prior art unless used withexceptional skill, will spread a lm of uneven thickness.

The rubber used in my applicator is preferably cut from a sheet ofuniform thickness, and will bend at a right angle with the slightestpressure at the line Where it emerges from the stem.

In View of the fact that sheet rubber or thin rubber of uniformthickness, no matter how made, produces a better wiper, the narrow slotin the end of the rigid stem appears to be the best mode of attachment.The rubber piece can be bent sharply where it emerges from this straightslot and will bend and otherwise function in the same way regardless ofthe direction of movement of the stem.

Rubber is the preferred material from which to make the wiper blade, butsome other material having characteristics suitable to the purpose ofthis invention may be employed.

While my applicator is especially adapted to the spreading of semi-iiuidand liquid adhesives, it may also be used for spreading other materialswhich likewise should be spread in thin uniform films.

It should be understood that this invention is susceptible of somevariation without departing from the spirit and scope of the inventiondened in the following claims.

Having shown and described my invention, I claim:

1. In combination, an adhesive container, a cover member therefor, arigid wooden stem having a squared end secured to the inner surface ofsaid cover solely by a nail or the like and extending substantially tothe bottom of the container, and a thin piece of highly flexible sheetrubber of substantially uniform thickness and greater width than thestem secured to the lower end portion of said stem and protrudingtherebeyond a short distance to receive and spread an adhesive, saidstem being of such length that when the cover is positioned on thecontainer the rubber applicator wipes the bottom of the container.

2. In combination, an adhesive container, a cover member therefor, arigid stem connected to the inner surface of said cover and extendingsubstantially to the bottom of the container, the lower end of the stemhaving a slot and a thin piece of highly flexible sheet rubber ofsubstantially uniform thickness secured in said slot and protrudingtherebeyond a short distance to receive and spread an adhesive, saidstern having a squared end for being secured solely to the inner surfaceof the cover by a small nail or the like piercing the cover and thestem.

3. In combination, an adhesive container, a flat-topped cover membertherefor, a rigid wooden rod secured to the inner surface of said coverby means of a flat-headed nail or the like extending through the cover,and a piece of highly ilexible rubber of substantially uniform thicknesssecured to one end portion of said stem and protruding therebeyond ashort distance to receive and spread an adhesive.

4. In combination, an adhesive container, a cover member therefor, aWooden rod having an end opening slot in one end portion thereof andhaving its other end secured against the inner surface of said cover bymeans of a nail or the like, and a thin piece of highly flexible rubberof substantially uniform thickness secured in said slot and protrudingbeyond the rod a suicient distance to receive adhesive for spreading.

FRANKLIN B. BAKER.

